/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.beam.sdk.io.aws2.kinesis;

import java.util.Comparator;
import java.util.Optional;
import java.util.stream.Stream;
import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
import org.joda.time.Instant;

/** Time conversion utilities. */
@SuppressWarnings({
  "nullness" // TODO(https://github.com/apache/beam/issues/20497)
})
public final class TimeUtil {

  public static java.time.Instant toJava(Instant timestamp) {
    return Optional.ofNullable(timestamp)
        .map(t -> java.time.Instant.ofEpochMilli(t.getMillis()))
        .orElse(null);
  }

  public static Instant toJoda(java.time.Instant instant) {
    return Optional.ofNullable(instant).map(t -> new Instant(t.toEpochMilli())).orElse(null);
  }

  static Instant minTimestamp(Stream<Instant> timestamps) {
    return timestamps.min(Comparator.naturalOrder()).orElse(BoundedWindow.TIMESTAMP_MAX_VALUE);
  }

  private TimeUtil() {}
}
